Rotary pump



July 28, 1931. l. H. wlLsEY 1,816,508

` ROTARY PUMP Filed July 9, 1927 2 Sheets-Sheet l .i Q mgggnnmw July 2s', 1931. l. H. wlLsEY 1;s16,5os

ROTARYPUMP Filed July 9, 1927 2 Sheets-Sheet 2 Patented July 28, 1931 UNITED STATES y PATENT OFFICE IRiVEN H. WILSEY, OF CHICAGO, ILLINOIS, ASSIGNOR TO JAMES B. TUTHILL, OF

CHICAGO,

ILLINOIS ROTARY PUMP Application led July 9,

My invention relates to improvements in rotary pumps, particularly rotary pumps of the type in which a pinion is mounted in mesh with and eccentrically to an internal gear rotor and a cut-off crescent-shaped partition is'disposed between the spaced peripheral surfaces .of the pinion and the rotor.`

Heretofore in pumps of the above mentioned type, there have commonly been prolO vided inlet and outlet passages opening respectively to opposite sides of the periphery of the rotor, and two diametrically opposed lands in peripheral engagement with the rotor in a median plane between said passages. In operation, the Huid in the inlet passage enters the rotor peripherally through the spaces between the vanes, is carried by the interdental spaces in the pinion and the rotor past the crescent-shaped partition and adjaf0 cent land, and is then discharged into the outlet passage.

Heretofore, pumps of this type have been subject to serious limitations and disadvantages. For example, at high rotor speeds, it

i5 is `extremely difficult for the fluid in the inlet passage to enter peripherally the quickly passing interdental spa-ces and thereby to fill completely the suction side of the rotor. This is due in part to the inadequate peripheral in- 33 let area which even at moderate speeds does not allow sulicient time for the fluid to fill the suct-ion space. As the speed of the rotor increases, time, which is a function of the inlet area, becomes less and less a factor, since the speed of the peripheral openings of the interdental spaces tends to resist the entrance of fluid thereto. At high speeds this dificulty is greatly increased by the action of centrifugal force which opposes the suction i0 created by the separating action of the teeth or vanes ofthe pinion and the rotor, and which tends to evacuate the interdental spaces. As a result, the pump is inefficient in operation, is limited in speed, and at eXtreme- 5 ly high speeds practically fails.

The primary object of the present invention resides in the provision of a new and improved pump of the above mentioned general type in which large inlet and discharge areas are provided giving ample time for the fluid 1927.v serial No. 204,467.

to pass to` and from the rotor, in which the inlet and discharge areas are not interrupted by the rotor vanes, and in which the entrance of Huid to the rotor is not impeded by the shearing action of the rotor vanes or by the action of centrifugal force.

A further object is to provide a novel rotary gear pump in which the interdental spaces are closed at the periphery of the rotor, and in which the -inlet and discharge passages open to one end of the rotor.

A general object of the invention is to provide a new and improved rotary gear pump which will operate eiiciently over a Wide range of speeds and at high speeds, which is simple and inexpensive in construction, and in which there is no addition of tolerances tending to reduce accuracy in construction.

Still another object resides in theprovision of a novel uniflow pump which operates quietly, in which there is no substantial leakage, and in which means is provided for taking up Wear to prevent leakage.

A further object resides in the provision in a pump of the above character of a movable `end land which yieldingly engages one end of the'rotor at a point diametrically opposite the crescent-shaped partition and between thc inlet and outlet passages. The back of this land may be vented to the suction side of the pump casing to provide a pressure relief pump, or may be vented to the discharge side of the pump to provide a wear compensating pump.

Another object resides in the provision of a tandem land, one back end area of which is vented to the discharge passage and the other back end area of which is vented to the inlet passage so as to obtain a balanced condition at high speeds.

A further object resides in the provision of a crescent-shaped partition which is pivotally secured Within the casing, and which will adjust itself on its pivot to compensate for wear.

Another object resides in the provision of novel means for preventing leakage along the rotor shaft.

A more specific object resides 'in thel provision of a fluid collecting lamination about Another object resides in the specific construction of the means for closing the periphery of the rotor to the inlet and disy charge passages.

Further objects and advantages will becomefapparent as the description proceeds.

In the accompanying drawings, Figure 1 isa left end View of a pump embodying the features of my invention. f

Fig. 2 is a right end viewof the pump.

Fig. 3 is a longitudinal sectional view taken along line 3-3 of Fig. 1.

Fig. 4 is an inslde view of the, cover for the pump casing.

Fig. 5 is a sectional View taken along line 5-5 of Fig. 3. i

Fig. 6 is a view similar to Fig. 5, but showing a modified form of the pump.

Fig. 7 is a fragmentary sectional view of the pump casing taken along line 7-7 of Fig. 2.

Fig. 8 is a fragmentary sectional view taken along line 8-8 of Fig. 1.

Fig. 9 is a view similar to Fig. 4, but of the modification shown in Fig. 6.

Fig. 10 is an axial sectional View of a modified form of rotor. j l

While the invention is susceptible of various modifications and alternative constructions, I have shown in the drawings and will herein describe in detail the preferred embodiment, but it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit and scope of the invention as expressed in the appended claims.

Referring more particularly to the drawings, the exemplary embodiment of the invention consists of a pump casing 10 which l is formed integral' with a suitable base 11,

and which preferably is cylindrical in shape. The interior of the casing 10 is formed with a cylindrical chamber 12. Of the casing 10, one end is closed by a fixed head 13' preferably formed integral therewith, and the other end is normally closed 'bya removable head or cover 14 secured thereto by any suitable means, such as a plurality of screw bolts 15. The head 13 is formed with an axial outwardly projecting bearing hub 16.

Rotatably mounted in the cylindrical chamber 12 is a rotor 17 which is provided with a drive shaft 18 adapted to be connected to a suitable source of power (not shown). The shaft 18 extends outwardly through the bearing hub 16, and in the present instance through a suitable packing 19 and a packing gland 20 in the outer end of the hub. The

` gland 2O is clamped tightlyvagainst the packing 19 by means of a bifurcated spring clamp therethrough, and preferably are closed by a y ring 25 disposed between the inner peripheral surface of the chamber 12 and the periphery of the rotor 17. The ring 25 may be rigidly secured in any suitable manner, as by a tight press, to either the casing 10 or the rotor 17 Preferably, as shown in Fig. 3, the ring 25 is separately disposed with a close fit between the casing 10 and the rotor 17 so as to adapt it to creep or slip and thereby avoid excessive wear at any one point. This construction provides a tight fluid seal. Inl the modified form of rotor shown in Fig. 10, the ring 25 is formed integral with the vanes 24, thereby constituting the rotor an internal gear with `closed roots. In this form, the plate 23 is formed separate of the vanes of the rotor 17, and is tightly secured in an annular notch 26 in the inner end of the inner periphery of the rotor.

Mounted on a stub shaft 27, which is journaled eccentrically to the shaft 18 in a hub 28 in the cover 14,is an idler pinion 29 which rests snugly against thefront end of the plate 23 and the teeth or vanes 30 of which mesh at one side with the vanes 24.' The other side of the pinion 29 is separated from the vanes 24 by a crescent-shaped projection or partition 3l extending inwardly from the cover 14. The partition 31 bears against the inner ends of the varies 24 and the outer ends of the vanes 30, and the inner and outer sur* faces of the partition conform respectively to the curvatures of the pinion 29 and of the rotor 17. The partition may have blunt ends, as shown in Fig. 5, or may have pointed ends as shown in Fig. 6. Preferably the partition 31' is separate from the cover 14, and is secured thereto by means of -a pivot pin 32. If wear occurs,-the pressure in the discharge side of the pump will tilt the opposite ends of the partition 31 about the pivot pin 32 respectively against the vanes 24 and 30 so as to retain a good fluid seal.

Fluid is admitted to and discharged from one` end of the rotor 17 and the interdental spaces between the vanes 24 and 20. Preferably fluid passes to and from rotor 17 through suitable chambers in the cover 14. In the present instance, the inner face of the cover 14 is formed in opposite sides' with two large to the spaces and 36 defined by the rotor 17, the pinion 29 and the partition 31, and are substantially coextensive in area therewith. The free ends of the chambers 33 and 34, opposite the partition 31 are separated by a narrovvr cut-off portion 37 formed integral with the cover. Suitable inlet and discharge passages 38 and 39 which are formed in the cover 14 and which are adapted to be connected in any desired line (not shown), open respectively into the chambers 33 and 34.

To prevent leakage past the cut-oli portion 37 due to wear, a suitable land is slidably mounted in this portion for engagement with the front ends of the rotor 17 and the pinion 29. Preferably, this land comprises alarge pin 40 and a small pin 41 arrangedv in tandem and slidably mounted in a bore 42 conforming thereto. A coil spring 43 is disposed in the inner end of the bore 42 and tends to press the land against theorotor 17 and the pinion 29. The inner end of the pin 40 is vented through a suitable bleed 'passage 44 to the inlet chamber 33, and the inner end of the pin 41 isvented through a suitable bleed passage 45 tothe iuid discharge chamber 34. Suitable bleed valves 46 and 47 are provided respectively in the passages 44 and 45.

Means is provided for preventing leakage of Huid along the shaft 18. Thls means preferably comprises a labyrinth groove 48 formed in the bore through the hub 16. Vent passages 49 and 50 (see Fig. 7) lead respectively from opposite sides of the labyrinth groove 48 to the front face of the casing 10,

' and are adapted to open respectively into ther leakage along the shaft.

vpassages 51 and 52 leading to the inlet chamber 33 and the discharge chamber 34. Disposed between the casing 10 and the cover 14 is a suitable gasket 53having a single port 54 adapted to connectone of the passages 49--50 to one of the passages 51-52 The gasket 53 is provided with an arrow 55 which is so arranged that if it is pointing in the direction ofrotation of the rotor 17 the port 54 will connect the labyrinth groove 48 to the suction side of the pump, and the gasket will close the other of the passages 49-50. It will be evident that any fluid escaping along the shaft 18 into the labyrinth groove 48 will be returned to the suction side of the pump, and that the liquid in the labyrinth groove will serve as a seal to prevent fur- In operation. assuming that the rotor 17 is being-driven clockwise as viewed in Fig. 1, fluid is drawn through the passage 38 and the chamber 33 into the space 35. The inlet area is large, and is uninterrupted by the vanes 24 so that the suction space 35 of the rotor fills completely even at very high speed. Since the periphery of the rotor is closed by the ring 25, centrifugal force will be ineffectual to evacuate the interdental spaces between the vanes. Fluid from the spacel 35 is carried by the rotor 17 and the pinion 29 past the partition 31, and is then discharged into the space 36 and chamber 34. By opening the valve 44, the land may be vented to the suction side of the pump to obtain a pressure relief pump; and by opening the valve 45, the land may be vented to the pressure side of the pump to obtain a balanced land. It will be evident that I have provided an extremely simple pump which will operate eiiciently at all speeds. which is not subject to leakage, in which wear is minimized and compensated for, and which is inexpensive and accurate in construction, there being no addition of tolerances. l

I claim as my invention: 1. A lrotary machine havingin combination, a rotor having internal vanes, the outer ends of the interdental spaces of which are closed to the passage of fluid peripherallyy said pinion. spaced inlet and outlet passages opening at opposite sides of said partition to one end of said rotor, and a movable end land yieldingly engaging said end of said rotor between said passages and diametrically op- .'posite to said partition.

, 2. A rotary machine having, in combination, a rotor having internal vanes, the outer ends of the interdental spaces of which are closed to the passage of fluid peripherallythe-reto or therefrom, a pinion eccentrically related to said rotor and meshing therewith, a partition located between said rotor and said pinion, spaced inlet and outlet passages opening at yopposite sides of said partition to one end o land yieldingly engagingf said end of said rotor between said passages and diametrically opposite to said partition, and a passage for'venting the back area of said land to one of said passages.

3. A rotary machine having, in combination, a rotor having internal vanes, the outer ends of the interdental spaces of which are closed to the passage of fluidperipherally thereto or therefrom, a pinion eccentrically related to said rotor and meshing therewith, a partition located' between said rotor and said pinion, spaced inlet, and outlet passages opening at opposite sides of said partition to one end of said rotor, a movable end land yieldingly engaging said end of said rotor between said passages and diametrically opposite to said partition, and a passage for venting the back area of said land to said inlet passage.

4. `'A rotary machine having, in combination, a rotor having peripherally spaced interna-l vanes on one end, the outer peripheral ends. of the interdental spaces of which are said rotor, and a movable end closed to the passage of fluid, a pinion eccentrically related to said rotor and meshing therewith, a partition located between said rotor and said pinion, a movable tandem land yieldingly engaging said end of said rotor and located diametrically opposite said partition, inlet and discharge passages opening respectively at opposite sides of said partition and said land to the ends of said vanes, means for venting one back area of said land to said inlet passage, and means for venting the other back area of said land to said discharge passage.

5. A rotary machine having, in combination, a rotor having peripherally spaced internal vanes on one e'nd, the outer peripheral ends of the interdental spaces of which are closed to the passage of fluid,a pinion eccentrically related to said rotor and meshing therewith, a partition located'between said rotor and said pinion,'a movable tandem land yieldingly engaging the ends of said rotor vanes and located diametrically opposite said partition, inlet and discharge passages opening to the ends of said vanes at opposite sides of said partition and said land, and means for selectively venting one back area of said land to said inlet passage, or the other back' area of said land to said discharge passage, or both of said back areas respectively to said passages.

6. A rotary machine having, in combination, a casing, a rotor journaled in said casing and having a. plurality of peripherally spaced vanes on one end, a pinion eccentrically related to said rotor and meshing therewith, a partition located between said rotor and said pinion, said partition being pivotvally mounted in said casing, and inletand discharge passages opening to said rotor.

7 A rotary machine having, in combinat1on, a casing, a cover closing one end of saidf` casing, a rotor journaled in said casing and having a plurality of peripherally spaced end vanes, a pinion eccentrically related tol said rotor and meshing therewith, a partition` located between Vsaid pinion and said rotor, said partition being pivotally mounted in said end of said casing, and inlet and discharge passagesopening to the ends of said vanes. v

8. A rotary machine having, in combination, a casing having a hub on one end, a cover closing the other end of said casing, a rotor having a shaft journaled in said hub, said rotor having avplurality of peripherally spaced vanes, a pinion eccentrically related to said rotor and meshing therewith, a partition located lbetween said rotor and said pinion, inlet and discharge passages opening through said cover and at opposite sides of said partition to opposite sides of one end of said rotor', a labyrinth groove for collecting fluid leaking along said shaft, a pair of vent passages extending from opposite sides of said labyrinth groove to said first mentioned passages, and a reversible gasket disposed between said casing and said cover, said gasket` said rotor having a plurality of peripherally y spaced vanes, a pinion eccentrically related to said rotor and meshing therewith, a partition located between said rotor and said pinion, inlet and discharge passages opening through said cover and at opposite sides of said partition to opposite sides of one end of said rotor, a labyrinth groove formed in the bore of said hub for collecting fluid leaking along said shaft, a pair of vent passages extending from opposite sides of said labyrinth groove to said first mentioned passages and a gasket disposed between said casing and said cover, said gasket having an opening for one of said vent passages and serving to interrupt the.

other of said vent passages, and being reversible to selectively open either of said vent passages.

10. A rotary machine having, in combination, a rotor having internally disposed vanes, a pinion eccentri/cally related to 'said rotor and meshing therewith, a partition located between said rotor and said pinion, spaced inlet and outlet passages opening to said rotor at opposite sides of said partition, and a movable end land yieldingly engaging one end of said rotor between said passages.

11. A rotary machine having, in combination, a casing havinga bearing hub, a rotor having a plurality of internal gear teeth, a

pinion eccentrically related to said rotor and meshing therewith, a partition located between `said rotor and said pinion, inlet and discharge passages opening respectively to opposite sides of said rotor, a shaft for driving 4the rotor and pinion assembly, said shaft being journalled in said hub, Y a labyrinth groove for collectin Huid leaking from said casing along said s sages extending from said labyrinth groove respectively to said inlet and discharge passages, and means for closing either one of said vent passages.

In testlmony whereof, I have hereunto affixed my signature.

IRVEN H. WILSEY.

aft, a pair of vent pas- 

